Conductor centering arrangement for traveling field tube



10, 1964 GUSTAV-ADOLF CLASSE 3, 5 ,845

CONDUCTOR CENTERING ARRANGEMENT FOR TRAVELING FIELD TUBE Filed Sept. 26,1960 l f I! Fig I G ST/W-ADOLF CLASSE Af/omqys Jnvenfor:

United States Patent 3,156,845 CONDUCTUR CENTERING ARRANGEMENT FURTRAVELING FIELD TUBE Gustav-Adolf Classe, Ulrn (Danube), Germany,assigner to Telefunlren Gesellsehaft rnit heschriinirter Haftung,

Hannover, Germany Filed Sept. 26, 1960, Ser. No. 58,248 Claims priority,application Germany Sept. '29, E59 Claims. (Cl. SIS-6.5)

The present invention relates to an improvement in traveling fieldtubes, more particularly, to an arrangement for centering the spiralconductor within a plurality of insulating bars spaced around theperiphery of the conductor.

It has been previously known to position a plurality of insulating barsaround the spiral conductor of a traveling field tube in order tosupport the conductor. This arrangement resulted in rigidly mounting thespiral conductor to facilitate the conducting of the beam of electronstherethrough.

An alternative structure comprised the mounting of the spiral conductorbetween ceramic insulating bars with metal clamps mounted on theinsulating bars and secured together by spot-welding. This arrangementwas inherently disadvantageous as it rendered ditl'icult the accurateadjustment of the several insulating bars. In addition, the use ofspot-welds produced severe stresses and strains which, in turn, caused adisplacement of the contact points between the insulating bars and themetal clamps.

The present invention is directed to improving the above-describedarrangement so as to eliminate the disadvantages thereof. Accordingly,this invention provides an improved arrangement for mounting the spiralconductor within a plurality of insulating bars which surround theconductor.

The present invention essentially comprises a pair of tensioning ringswhich are rotatable with respect to each other and which surround theassembly of the spiral conductor and the insulating bars. The tensioningrings are in face-to-face relationship and have a plurality ofsubstantially spiral-shaped cam surfaces on the edges of the centralopenings. These cam surfaces correspond in shape and position to theinsulating bars. The cam surfaces are so shaped that rotation of therings in one direction with respect to each other will urge theinsulating bars against the spiral conductor so as to support theconductor in its central position.

it is therefore the principal object of this invention to provide anovel and improved arrangement for centering the spiral conductor withina plurality of insulating bars spaced about the periphery of theconductor in a traveling field tube.

It is another object of this invention to provide a simple and effectivestructure for centering the spiral conductor within a plurality ofinsulating bars spaced about the periphery of the conductor in atraveling field tube, whereby the components of the structure can belocked in position with respect to each other.

It is a further object of this invention to provide an arrangement for atraveling field tube for centering the spiral conductor between aplurality of insulating bars wherein the arrangement comprises a pair offlat members adjustable with respect to each other.

It is an additional object of this invention to provide an arrangementfor a traveling field tube for centering the spiral conductor between aplurality of insulating bars, which arrangement can be selectivelypositioned along the length of the spiral conductor.

Other objects and advantages of this invention will become apparent uponreference to the accompanying description when taken in conjunction withthe following drawings, wherein:

FIGURE 1 is an overall schematic view of a traveling field tube whichembodies the present invention;

FIGURE 2 is a plan view of the tensioning ring ar rangement and isessentially a transverse sectional view of the tube of FIGURE 1, but inenlarged scale, and

FIGURE 3 is an elevational view of the tensioning rings illustrated inFIGURE 2.

Proceeding next to the drawings, a specific embodiment of this inventionwill be described with particular reference to FlGURE 1 where there isgenerally illustrated a traveling field tube 1 in which is embodied thepresent invention. This tube comprises a casing 2 which is anessentially vacuumsealed envelope. At one end of the envelope is asource of a stream of electrons or an electronic emitter 3 and at theother end of the tube is a target i.

A conventional spiral conductor 5 extends between the emitter and thetarget and is essentially positioned along the central longitudinal axisof the tube. There is a plurality of insulating bars 6 which are made ofceramic and which engage the outer periphery of the spiral conductor soas to support the conductor in this desired position. In this particularembodiment of the invention three insulating bars are employed.Positioned along the length of the spiral conductor are two pairs oftensioning rings 7.

Proceeding next to FIGURE 2, the tcnsioning ring 7 is essentially a hatannular member having an outer periphery 8 and a central opening 9. Theedge or the central opening 9 is formed to provide three equally spacedcam surfaces ill which correspond in number and position to theinsulating bars. The distance bet een the cam surfaces iii and thecenter of the tensioning rings, as indicated at ll, gradually changes sothat in efiect the shape of the cam surfaces is that of a spiral.

The two tensioning rings comprising a pair are positioned inface-to-face relationship such as can be seen in FIGURE 3. The camsurfaces ill of the rings of a pair are in reverse relationship, as isshown in FIGURE 2. As a result of this reverse relationship, rotation ofthe nearer ring, as viewed in FIGURE 2, in a clockwise direction withrespect to the further ring will urge the insulating bars 6 against theperiphery of the conductor 5.

Conversely, rotation of the nearer ring of FIGURE 2 in thecounter-clockwise direction will release the insulating bars fromengagement-with the spiral conductor. Since the cam surfaces are soselected to give clearance between the insulating bars and the camsurfaces when the tensioning rings have been rotated to release theinsulating bars, a pair of tensioning rings can he slid over theinsulating bars to be positioned at any point along the length of thetube. By spacing the several pairs of rings from each other in aparticular manner, the highfrequency characteristics of the tube can bevaried. In addition, the tensioning rings may be used for suppressingmany undesired forms of oscillation.

Another feature of this invention is the provision of means for lockingtogether the pair of tensioning rings in a desired relationship. Thismay be done by spotwelds such as at 12. on the outer peripheries of thetensioning rings.

.In addition, if the slopes of the cam surfaces 10 are made sufiicientlygradual, the tensioning ring arrangement will be self-locking when therings are rotated with re K areaeee 3: spect to each other when theinsulating bars are urged against the conductor. 7

A structure is also provided on the rings for rotatively displacing therings with respect to each other. One form of this structure is merelythe making of holes or openings in the rings Which holes then receivetools for rotating the rings.

As can be seen in FIGURE 3, bossed portions 15 are provided on the outerflat lateral faces of the tcnsioning rings. These bossed portions havedepressions or recesses 14 for also receiving a tool for rotativelydisplacing the rings.

In addition, notches 15 may be provided in the outer periphery 8 of thetensioning rings for receiving tools for rotating the rings.

To ensure constant operating conditions within the tube the tensioningrings '7 are constructed of a material such as copper, so that thepressure is exerted by the insulating bars upon the spiral conductorelements substantially throughout the entire range of temperaturesencountered within the tube. In addition, judicious selection of theten'sioning ring material can be employed to influence the magneticfocusing field of the tube, so as to focus the beam of electrons,depending on Whether a ferro-magnetic material such as iron or anon-magnetic material such as copper is used.

Thus it can be seen that the present invention has disclosed a simpleand effective arrangement for centering the spiral conductor which ismounted between a plurality of insulating oars spaced about theperiphery thereof. Further, this arrangement may be made self-locking soas to eliminate any necessity of spot-welding of the rings in a fixedrelationship to each other. In addition, the locking arrangementfacilitates a rapid adjustment of position of the tensioning rings withrespect to the length of the tube.

It Will be understood that this invention is susceptible to modificationin order to adapt it to different usages and conditions and,accordingly, it is desired to comprehend such modifications within thisinvention as may fall Within the scope of the appended claims.

Remarks.Traveling field tube means traveling Wave tube. Spiral conductormeans helical wave guide.

What is claimed is:

1. In a traveling field tube, a spiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of rings in face-to-face relationship surrounding said insulatingbars, the inner edge of each ring having a plurality of cam surfacescorresponding in number and position to said insulating bars, thecorresponding cam surfaces of said rings being in reverse relationshipso that rotation of said rings in one direction with respect to eachother Will urge said bars against said conductor.

2. In a traveling field tube, a spiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of flat annular members in face-to-face relationship and havingopenings therein with said conductor and bars passing therethrough, theinner edges of said openings having a plurality of spiral-shaped camsurfaces corresponding in number and position to said insulating bars,the corresponding cam surfaces of the annular members being in reverserelationship to each other so that rotation of said members with respectto each other 1n one position will urge said bars against.

said conductor.

3. In a traveling field tube, aspiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of rings in face-to-face relationship surrounding said insulatingbars, the inner edge of each ring having a plurality of spiral-shapedcam sur-. faces corresponding in number and position to said in sulatingbars, the corresponding cam surfaces of said rings being in reverserelationship so that rotation of said rings in one directionWithrrespect to each other will urge said bars against said conductor,and means for locking said rings with respect to each other.

4. In a traveling field tube, a spiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of rings in face-to-face relationship surrounding said insulatingbars, the inner edge of each ring having a plurality of spiral-shapedcam surfaces corresponding in number and position to said insulatingbars, the corresponding earn surfaces of said rings being in reverserelationship so that rotation of said rings in one direction withrespect to each other Will urge said bars against said conductor, saidrings being spot-Welded in fixed relationship to each other. 7

5. In a traveling field tube, a spiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of rings in face-to-face relationship surrounding said insulatingbars, the inner edge of each ring having a plurality of spiral-shapedcam surfaces corresponding in number and position to said insulatingbars, the corresponding cam surfaces of said rings being in reverserelationship so that rotation of said rings in one direction Withrespect to each other will urge said bars against said conductor, saidrings having bosses with recesses therein for receiving a tool used forrotatively displacing said rings with respect to each other.

6. In a traveling field tube, a spiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of rings in face-to-face relationship surrounding said insulatingbars, the inner edge of each ring having a plurality of spiral-shapedcam surfaces corresponding in number and position to said insulatingbars, the corresponding cam surfaces of said rings being in reverserelationship so that rotation of said rings in one direction withrespect to each other will urge said bars against said conductor, saidrings having notches on the peripheries thereof for receiving a toolused for rotatively displacing said rings With respect to each other.

7. In a traveling field tube, a spiral conductor, a plurality ofinsulating bars outwardly of said conductor and supporting the same, apair of rings in face-to-face relationship surrounding said insulatingbars, the inner edge of each ring having a plurality of spiral-shapedcam surfaces corresponding in number and position to said insulatingbars, the corresponding cam surfaces of said rings being in reverserelationship so that rotation of said rings in one direction Withrespect to each other will urge said bars against said conductor, andmeans on said rings for receiving a tool used for rotatively displacingsaid rings With respect to each other.

8. An arrangement for centering a spiral conductor of a traveiing fieldtube'within insulating bars supporting the same and comprising a pair offiat'annular members in face-to-face relationship and having openingstherein with the conductor and insulating bars passing therethrough, theinner edges of said openings having a plurality of spiral-shaped camsurfaces corresponding in number and position to said insulating bars,the correspending cam surfaces of the annular members being in reverserelationship to each other so that rotation of said members with respectto each other in one position Will urge said bars against saidconductor.

9. An arrangement for centering a spiral conductor of a traveling fieldtube within insulating bars supporting the same and comprising a pair offlat annular members in face-to-face relationship'and having openingstherein With the conductor and insulating bars passing therethrough, theinner edges of said openings having a plurality of spiral-shaped camsurfaces corresponding innurnber and position to said insulating bars,the corresponding cam surfaces of the annular members being in reverserelationship to each other so that rotation of said membersWlllI'IESPECt to each other in one position'will urge said bars againstsaid conductor, said flat annular members having bosses on the outerlateral surfaces the'reof with each boss having a recess therein forreceiving a tool a a used for rotatively displacing said annular memberswith References Cited in the file of this patent respect to each other.

10. In a traveling field tube, a spiral conductor posi- UNITED STATESPATENTS tioned substantially along the central axis of the tube, a2,001,153 Packman May 14, 1935 plurality of insulating bars extendinglongitudinally of said 5 2,806,170 Bianculli Sept. 10, 1957 tube andengaging the periphery of said spiral conductor, 2 317 037 Peter Dec 171957 a pair of fiat circular annular members having central openingstherein with said insulating bars and spiral conductor passingtherethrough, the edges of said central openings having a plurality ofequal spiral-shaped earn 19 2,828,440 Dodds et al Mar. 25, 1958 FOREIGNPATENTS surfaces corresponding in number and position to said g? Great ff 7! 1951 insulating bars, the corresponding cam surfaces of said807,337 Great Bntaln 1959 circular members being in reverse relationshipso that 9 ,9 4 Germany Sept. 12, 1955 rotation of said annular membersin one direction with 1,052,583 Germany Mar. 12, 1959 respect to eachother Will urge said insulating bars against 15 the periphery of saidconductor.

1. IN A TRAVELING FIELD TUBE, A SPIRAL CONDUCTOR, A PLURALITY OFINSULATING BARS OUTWARDLY OF SAID CONDUCTOR AND SUPPORTING THE SAME, APAIR OF RINGS IN FACE-TO-FACE RELATIONSHIP SURROUNDING SAID INSULATINGBARS, THE INNER EDGE OF EACH RING HAVING A PLURALITY OF CAM SURFACESCORRESPONDING IN NUMBER AND POSITION TO SAID INSULATING BARS,